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Solar streetlamps experiment hits Vancouver parks

They're curvy, a tad futuristic, and, upon inspection, completely impractical. But there's a method, and a virtuous principle, behind the solar streetlights of Vancouver.

Perched in a few spots across the city – Strathcona Park, Sunset Beach, and soon, Queen Elizabeth Park – these streetlamps symbolize a faith in the future of energy savings and solar power in Metro Vancouver.

To advocates of green living and infrastructure, solar panels on a streetlamp pole is an exciting sight. What could be better than harnessing energy from the sun to light local parks and provide safety and security?

Because of their limitations – both in price and efficiency – these lamps can't be trumpeted as a pioneering breakthrough. Gruja Blagojevic, an engineer in charge of electrical design for the city of Vancouver, describes them as pricey symbols of leadership by the city.

"We wanted to have those locations that are high exposure to public and so on, to show we are leading our way to use solar energy," says Blagojevic.

The city has been discussing the benefits of solar power on municipal and park land for almost a decade. Talk turned to action just two years ago, when the city partnered with the British Columbia Institute of Technology's Lou Stamenic, the head of the school's Research and Development and a specialist in photovoltaics, and BC Hydro's Technology Innovation manager Gary Hamer.

Each brought his own specializations and challenges to the task.

As a BC Hydro engineer, Hamer looks closely at efficiency and energy conservation. As a city employee, Blagojevic pays attention to the sensitivities of parks board commissioners, who have the final say on the location of the lamp poles.

"The lamps [can be used as] a proof of concept," says Hamer. "Many times new technologies don't make any economic sense but we want to show that we are doing the right thing and will invest certain amount of funds to promote that."

How they work

Aside from their curious look, the technology behind these solar streetlights is much more complex than it appears.

The curve of the pole helps to bring the surface area of the photovoltaic, or solar panels, perpendicular to the sun's position at the time of day when the sun's rays are most likely to hit the panels. Those solar panels contain solar cells that convert the sun's rays into electrical power.

The next vital component in the structure is the underground battery that is charged in the daytime during sun exposure. Taking the pooch out for a late-night emergency outing? The lights illuminate as soon as they detect movement within 20 feet and stay lit for some time, according to Hamer. They stay illuminated for 15 minutes, then fade to a lower level.

Of course, there are more than a few bugs to work out.

Technology not yet cost-efficient

The cost of delivering this solution is about 10 times that of conventional streetlamps – at least under today's modestly-priced electricity rates in B.C. – says Hamer. Also, since B.C.'s sunshine is limited most months of the year, the panels must be placed specifically in south-facing areas.

"Proponents of solar power will tell you [solar energy] is free energy, and that's true," he says. "It's striking us all the time, so why not take advantage of it? But in order for photovoltaic panels to be cost-effective, we're going to have to see a doubling of the efficiency and a halving of the cost."

That may take many years, but it's doable, says Blagojevic. And being what's known as an "early adopter" has its bragging rights.

"New technologies are always very expensive at first," he says. "Someone had to buy the first LCD – television, didn't they?"